Drop BufReader in Deserialization of Consensus Objects

[Abeeujah]

The rust-bitcoin 0.32.4 release include the standardisation of deserialization methods to use Read over BufRead when decoding/deserializing consensus objects, this makes the buffered Read wrapper no longer needed and can now be dropped.

• deee085 Drops the usage of BufReader in Readable impl.
• b582ce1 Drops the buffered Read wrapper.

[ldk-reviews-bot]

I've assigned @valentinewallace as a reviewer!
I'll wait for their review and will help manage the review process.
Once they submit their review, I'll check if a second reviewer would be helpful.

[ldk-claude-review-bot]

The PR is small and surgical. Let me verify the change preserves the original "don't over-read" property and that the dependency supports the new API.

The Cargo.toml already requires bitcoin = "0.32.4" (lightning/Cargo.toml:42), which guarantees the Read-based consensus_decode API. The removed BufReader was, in normal operation, a pass-through (its fill_buf/consume were never called by rust-bitcoin, hence the debug_assert!(false)), and its read simply delegated to the inner reader. Passing r directly to the new Read-based decoder preserves the same byte-exact, no-over-read behavior. The use import correctly retains self/Read/Write, all of which are still used. No remaining references to BufReader/BufRead exist in ser.rs.

No issues found.

[ldk-reviews-bot]

👋 The first review has been submitted!

Do you think this PR is ready for a second reviewer? If so, click here to assign a second reviewer.